A chloroprene rubber is excellent in mechanical properties, weather resistance, flame retardancy, etc. and is widely used as a material for industrial rubber components. Properties required for such industrial rubber components are remarkably high, and one having the above properties such as mechanical properties, weather resistance and flame retardancy maintained and in addition, being excellent in ozone resistance and heat resistance is required.
As a means to improve ozone resistance of a chloroprene rubber, a technique of blending an epichlorohydrin polymer rubber and a vulcanizer (e.g. Patent Document 1), a rubber composition comprising an ethylene/propylene/diene copolymer rubber and an antioxidant blended (e.g. Patent Documents 2 and 3), etc. have been known.
As a means to improve heat resistance of a chloroprene rubber, a technique of blending a chloroprene rubber with an aluminum salt of a specific fatty acid (e.g. Patent Document 4) or a technique of blending a chloroprene rubber with specific carbon black, a zinc powder and a specific plasticizer (e.g. Patent Document 5) etc. have been known.    Patent Document 1: JP-A-2004-123887    Patent Document 2: JP-A-H09-291178    Patent Document 3: JP-A-H02-189342    Patent Document 4: JP-A-2005-281629    Patent Document 5: JP-A-2005-060581